1161491640540 has 96 divisors (see below), whose sum is σ = 4054661743104. Its totient is φ = 241348911360.

The previous prime is 1161491640511. The next prime is 1161491640571. The reversal of 1161491640540 is 450461941611.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1161491640492 and 1161491640501.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 125697939 + ... + 125707178.

It is an arithmetic number, because the mean of its divisors is an integer number (42236059824).

Almost surely, 2^{1161491640540} is an apocalyptic number.

1161491640540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1161491640540 is an abundant number, since it is smaller than the sum of its proper divisors (2893170102564).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1161491640540 is a wasteful number, since it uses less digits than its factorization.

1161491640540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251405147 (or 251405145 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 42.

The spelling of 1161491640540 in words is "one trillion, one hundred sixty-one billion, four hundred ninety-one million, six hundred forty thousand, five hundred forty".